Electrolytic refining or extracting process.



F. R. PYNE & H. NI. GREEN.

ELECTROLYTIC REFINING 0R EXTRACTING PROCESS.

APPLICATION FILED APR.2o,1915.

L 14.?98. Patented Aug. 3, 1915.

/v al@ @www iuErrEn sfrarns EEEEEE @Ernani FRANCIS R. PYNE, OFELIZABETH, AND I'IENRY M. GREEN,

ASSIGNORS T0 UNITED STATES METALS REEINING COIVIPHNY, OF

0E CHROME, NEW JERSEY, CHROME, 'NEW JERSEY, A CORPORATION 0F NEW JERSEY.

ELECTROLYTIC REFINING 0R EXTRACTING PROCESS.

Specification of Letters Patent.

Application led April 20, 1915. Serial No. 22,559.

To all whom t may concern.'

Be it known that we, FRANCIS R. PENE, residing in Elizabeth, county ofUnion, State of New Jersey, and HENRY M. GREEN, residing in Chrome,county of Middlesex, State of New Jersey, both citizens of the UnitedStates of America, have invented certain new and useful Improvements inElectrolytic Rening or Extracting Processes, of which the following is aspecification.

This invention relates to improvements in electrolytic refining orextraction processes, and aims to provide improvements therein.

Electrolytes are usually found to contain, or be composed of, severalconstituents, this being pricipally due to the fact that the substances,such as ores, bullion, ingots, etc., which are used in contact with theelectrolyte, usually contain several: compounds or It has been foundthat electrolytic solli- `tions, while the current is passing, stratify,

and that in electrolytes containing several constituents, the .separateconstituents will be found to be more concentrated in certain portionsor strata of the electrolyte than in other portions or strata, thedegree of stratification depending largely upon the rate of flow of thesolution through the electrolytic tank, and the strength of the electriccurrent. The primary constituent will accordingly be more concentratedin a stratum more or less distinct and separate from the stratum orstrata in which there is the greatest concentration of the secondaryconstituent or constituents.

Heretofore, with the purpose of avoiding, as far as practicable,stratification, and in order to avoid the accumulation of the secondaryconstituents in the tank, it has been the practice to provide a goodcirculation through the tank, and to introduce and withdraw the incomingliquid in suchmanner as to attain an even distribution, as far aspracticable, within the tank.

When operating under economical conditions, by the old method, thesolution issuing from the tank, contains a percentage of the primaryconstituent which is of commercial importance, and a percentage of thesecondary constituents which it may be desired to remove from theelectrolyte. It has heretofore been customary to treat a portion of theelectrolyte issuing from the first tank, 'or series of tanks, in asecond tank, or series of tanks, for the purpose of recovering furtherproducts from the primary constituent before recovering or removing thesecondary constituents. When the electrolyte reaches the second tank, orseries of tanks, in order to effect the recovery of further productsfrom the primary constituent and at the same time prepare for therecovery or removal of the secondary constituents, it is necessary-touse insoluble anodes which require a higher electric pressure in thesecond tank or series of tanks than in the first, thereby requiringproportionatelyy greater energy. The deposit in the second tank, orseries of tanks,

is usually inferior to that in the first, being of a second orintermediate grade. The electrolyte from the second tank, or series oftanks, rusually contains enough of thepri- -third clectrolytic tank, orseries of tanks,

and subjectedv to the action of the current in a similar manner, untilall or practically all of the primary constituent is removed. Thesecondary constituents are thereupon recovered or removed in yanysuitable way.

According to` the present invention, the electrolyte in the first tank,or tanks, is allowed to stratify, to a determined or desired degree, andthe solution issuing from the electrolytic tank is taken off in severalportions or strata. The portion of the electrolyte which is richest inthe primary constituent (and relatively poor in the other constituent orconstituents) is run of separately, and is either run back into thefirst tank or tanks, or into other tanks, wherein it may be treatedunder the same conditions as, or more advantageous `conditions than,

Patented Aug. 3, 1915,

in the firsttank. The portions of'the elec- 1 trolyte containing thegreater concentration of the secondary constituents are run offseparately or together, and are so poor in the principal constituentthat they may be immediately treated for the elimination of the primaryconstituent, and may then undergo further treatment for the recovery orremoval ofthe secondary constituent or products thereof.

The present invention provides a process whereby a greater output ofmerchantable product is obtained than heretofore, by enabling the secondtank or series of tanks to operate under conditions of electricalpressure and grade of product, similar to the first tank or series oftanks. Furthermore, by reason of the lower electric pressure which maybe employed in the second tank or series of tanks, there is a greatsaving of electrical energy.

The present 'invention will be described in greater detail withreference to the accompanying drawings.

Special reference will be made to the electrolytic refining of copper,though it is to be -understood that the invention is applicable toelectrolytic extracting and refining processes generally.

Figurel 1 of the drawing illustrates an electrolytic tank inlongitudinal vertical section, and Fig. 2 illustrates an example of asystem of tanks, in which the process may be carried out. V

A designates an electrolytic tank, and B an inlet. The anodes arepreferably composed of, or comprise, the substance which is to berefined. A solvent, or a solution containing the necessary constituentsof the electrolyte, is introduced into the tank. In thel electrolyticrefining ofcopper the anodes are usually made of unrefined copper, andcontain, beside copper, other elements, depending on the ores from whichthe copper was obtained, etc. For instance, the anodes may contain,vbeside copper, iron, nickel, arsenic, zinc, antimony, silver, gold,etc., separately, or more generally, some two or more together.'

Under the action of vthe electric current the anode is dissolved, thegreater part of the copper therefrom being deposited on the cathode,such constituents as are insoluble in the electrolyte settlingto thebottom of the tank-as slime,'and such constituents as are soluble, linthe electrolyte passing into solution and becoming a partthereof.However, during the passing of the electric current, a stratification ofthe electrolyte takes place, and, in the case of copper refining, forexample, it is found that the copper solution (primary constituent) ismost concentrated in the lower part of the tank, forming a lower strataas indicated at C. The solutions of the other substances (secondaryconstituents) which enter theelectrolyte are found most concentrated inla 'stratum or strata D above that o\f the concentrated primaryconstituent, z'. e. the concentrated copper solution. In order toprevent an excessive stratification of the electrolyte, whichisdetrimental to a proper working of the process, a circulation isproduced through the tank or tanks, and, in order to prevent anundesirable accumulation of the secondary constituents, a portion of thecirculated electrolyte is withdrawn for the removal or recovery of the.secondary constituents. The circulation may take yplace by reason of adifference inlevel between the solution in the tank or tanks and thesolution in the reservoir from which the tank or series of tanks issupplied.

According to the present invention, the4 circulation through the tankorl tanksconstituents are most concentrated. Other pipes l F1 may beprovided for leading off any particular fraction or stratum of theconcentrated secondary constituents. The concentrated primaryconstituents may also be led oftl in fractions of differentconcentration, if

desired. The portion of the electrolyte containing the highconcentration of the primary constituentmay be led back into the firstelectrolytic tank or series of tanks, or into other similar tanks. Theportion of the electrolyte containing thev high concentration of thesecondary constituents is preferably led to an electrolytic tank M orseries of tanks, and subjected to the action of the current for thepurpose of eliminating the primary constituent, for example the copper,

or may be led to other tanks for any desired treatment. Thestratification, and the concentrations of the constituents of theelectrolyte in the several strata, may be regulated by the degree offiow through the outlets, and more -especially by the relative degreesof flow through the separate outlets.

In the refining of copper, the tanks with vthe insoluble anodes used forthe intermediate and final treatment of the primary constituent of theelectrolyte, are usually operated at an electric pressure of about2..volts, and the copper deposited is usually of inferior grade.Accordingto the present invention, there is usually no necessity totreat the liquid issuing from the first tanks in intermediate tanks,using insoluble anodes for the purpose of eliminating the greaterportion of the primary constituent. The part of the electrolyte issuingfrom the rst tank or tanks containing the low concentration of theprimary constituent may be immediately treated for the elimination ofthe primary constituent, and the part of the electrolyte containing thehigh` concentration of the primary constituent may be returned to thefirst tank or tanks. A less number of tanks operating at high electricalpressure is therefore required than under the old methods, under similarconditions. There is a more efficient utilization of the electrolytictanks and there is a saving in energy. For example, in copper refining,the tanks with the soluble anodes are operated at a pressure of about .3volts and less.

That is claimed is l. In an electrolytic refining or extracting process,wherein the electrolyte contains more than one constituent, allowingstratification to take place to a determined or desired degree, andleading o portions of the electrolyte separately from different strata.

2. In an electrolytic refining or extracting process, wherein theelectrolyte contains more than one constituent, allowing stratificationto take place to a determined or desired degree, and leading off theelectrolyte separately at different levels.

3. In an electrolytic refining or extracting process, wherein the anodeis soluble and 'wherein the electrolyte contains a primary constituentand a secondary constituent, allowing stratification to take place to adetermined or desired degree, and leading off separately a portion ofthe solution from the stratum of the concentrated primary constituent.

4. In an electrolytic refining or extracting process, wherein the anodeis soluble and wherein the electrolyte contains a primary constituentand a secondary constituent, allowing stratification to take place to adetermined or desired degree, leading off separately a portion of thesolution from the stratum of the concentrated primary constituent, andleading off a portion of the solution from a stratum of the concentratedsecondary constituent.

In an electrolytic refining or extracting process, wherein the anode issoluble and wherein the electrolyte contains a primary constituent and asecondary constituent, allowing stratification to take. place to adetermined or desired degree, leading ofi separately a portion of thesolution from the stratum of the concentrated primary constituent, andleading off a portion of the solution from a stratum of the concentratedsecondary constituent, and directly treating said portion containing theconcentrated secondary constituent to eliminate the primary constituent.

6. In an electrolytic refining or extracting process, wherein theelectrolyte contains more than one constituent, allowing stratificationto take place to a determined or desired degree, leading off portions ofthe elec-y trolyte separately from different strata, and controlling therelative concentrations of the constituents in the several strata byregulating the flow of the separate outfiowing portions of theelectrolyte.

7 In an electrolytic refining or extracting process, wherein the anodeis soluble and wherein the electrolyte contains a primary constituentand a secondary constituent, allowing stratification to take place to adetermined or desired degree, leading off separately portions of thesolution from several levels, a portion being led ofi, from the stratumof the concentrated primary constituent, and returning the led-offportion of the electrolyte containing the concentrated primaryconstituent to the electrolytic tank.

8. In an electrolytic refining or 'extracting process, wherein the anodeis insoluble and wherein the electrolyte contains a primary constituentand a secondary constituent, allowing stratification to take place to adetermined or desired degree, and leading ofi' separately a portion ofthe solution from the stratum of the concentrated primary constituent.

9. In an electrolytic refining or extracting process, wherein the anodeis insoluble and wherein the electrolyte contains a primary constituentand a secondary constituent, a1- lowing stratification to take place toa determined or desired degree, leading off separately a portion of thesolution from the stratum of the concentrated primary constituent, andleading off a portion of the solution from a stratum of the concentratedsecondary constituent.

10. In an electrolytic refining or extracting process, wherein the anodeis insoluble and wherein the electrolyte contains a primary constituentand a secondary constitu- Y ent, allowing stratification to take placeto a determined or desired degree, leading 0E separately a portion ofthe solution from the stratum of the concentrated primary constituent,and leading off a portion of the solution Jfrom a stratum of theconcentrated secondary constituent, and directly treating said portioncontaining the concentrated secondary constituent to eliminate theprimary constituent. l

11. In an electrolytic refining or extracting process, wherein the anodeis insoluble and wherein the electrolyte contains a primary constituent`and a secondary constituent, allowing stratification to take place to adetermined or desired degree, leading off separately vportionsof thesolution from sevsigned our names inthe presence of two suberal levels,a portion being let oft1 from the scribing Witnesses.

stratum of the concentrated primary con.- FRANCIS R. PYNE. sttuent, andreturning the led-of portion of HENRY M. GREEN.

5 the electrolyte containing the concentrated Vitnessesz primaryconstituent to the electrolytio tank. WILLIAM C. WEBER,

In Witness whereof, We have hereunto JACOB ROTH.

